负载Zr(Ⅳ)的水解废弃皮革对氟离子的吸附性能

Adsorption of fluorion onto hydrolyzed leather waste impregnated with zirconium(Ⅳ)

将锆(Ⅳ)负载在通过氢氧化钠(Na OH)水解的粒状废弃皮革上制备出新型氟离子(F-)吸附剂。采用扫描电子显微镜(SEM)、X射线能量色散光谱分析(EDX)、X射线光电子能谱分析(XPS)、傅里叶变换红外吸收光谱分析(FTIR)等方法研究了该吸附剂对水溶液中F-的吸附特性及其吸附机理。结果表明:研究条件下,粒状废弃皮革与Zr(NO_3)_4·5H_2O最优的质量比为1:3;该吸附剂对F-的最优吸附p H为4;该吸附剂对F-的吸附等温线符合Langmuir方程,拟合得出对F-的饱和吸附量为30.56 mg·g^(-1);吸附动力学可用准二级动力学模型描述,属化学吸附,F-以离子交换的形式代替羟基(—OH)与吸附剂中的Zr(Ⅳ)结合形成稳定的化学键,从而达到吸附水溶液中氟离子的目的。

A novel adsorbent was prepared from hydrolyzed granular leather waste（ZHGLW） impregnated with Zr（Ⅳ） for fluorion removal. Fluorion adsorption performance and mechanism were investigated by scan electron microscope, energy dispersive analysis of X-ray, X-ray photoelectron spectroscope, and Fourier transform infrared spectroscopy. The results indicate that the optimal mass ratio of hydrolyzed granular leather waste and Zr（NO3）4·5H2O is 1：3 in this study. The maximum removal of fluorion is obtained at p H 3. The isotherm data fit the Langmuir isotherm model well and the obtained maximum fluorion adsorption capacity of the sorbent is 30.56 mg·g^-1. The kinetics of fluorion adsorption onto ZHGLW follows the pseudo-second-order model. Fluorion adsorption process is a chemisorption process, which can be described as that —OH is replaced by fluorion in the form of ion exchange and a stable chemical bond forms through fluorion and impregnated Zr（Ⅳ）. Thus, ZHGLW could be an efficient adsorbent for fluorion.